In many countries snakes represent a serious hazard to public health. Although antivenins (horse serum) are very effective in neutralizing lethal action of snake venom, they are not very effective in neutralizing the local tissue damaging activity of venom unless injected immediately. In crotaline envenomation (by rattlesnakes and copperheads) one of the most striking effects is local tissue damage such as edema, hemorrhage and myonecrosis. In severe cases of poisoning this local damage can result in the complete loss of an extremity or dysfunction of a finger, hand or entire arm or leg. Thus a person might survive the bite but remain disabled for life. Therefore it is highly desirable to develop a chemical treatment for local tissue damage which could be used in addition to antivenin to prevent local damage as well as systemic or lethal effects. Some people are sensitive to horse antiserum and cannot receive antivenin. A chemical treatment would be useful for these people. In order to develop a non-serum treatment for rattlesnake poisoning we are testing a variety of compounds for their ability to neutralize hemorrhagic, myonecrotic and lethal activities of rattlesnake venom.